Motoman Robot Handling and IMM Tending Automotive Powertrain Hardware

Motoman HP50 robot, equipped with multi-function gripper, unloads journals and link bars from a pallet on an infeed conveyor and unloads/loads molded parts from/to an IMM onto an outfeed conveyor.

Summary

Robot system meets or exceeds project requirements for automated insertion and removal of parts from IMM operation. Cycle time is 12 seconds, which is well within the 14 seconds of time allowed for load/unload operations (15.7 percent faster than requirement). Robot system increased productivity and throughput, as 70-second closed and mold transition cycle was reduced to 65 seconds. Flexible system handles variety of required part sizes and manual changeover is 15 minutes or less. Sensor checks gripper details, and also indicates proper part type and link bar orientation.

Project Challenges

Automate insertion and removal of parts from an injection molding machine (IMM) operation.
IMM press will be fully open and available to the robot for load/unload operations for 14 seconds. All executed operations, outside of the press load/unload operations, must be completed within the 70-second closed and mold transition cycle.
System will handle a variety of part sizes, ranging from approximately 36.6-82.5 mm (1.44"-3.25") L and from 46-52 mm (1.81"-2.05") H. Manual changeover between part types should not exceed approximately 15 minutes. Two sets of parts are molded per cycle; each set contains a journal and a link bar.

Motoman Robotics Solution

Motoman Robotics provided a custom HP50 machine tending solution, including:
Motoman HP50 robot with NX100 robot controller.
Additional XOI01 Discrete I/O module.
SPI Interface – for robot controller to IMM communication.
Robot base riser.
Allen-Bradley SLC 5/04 PLC and controls package.
Pallet infeed conveyor – 2.43-m (8-ft ) L powered roller type with brakes and blade stop.
90-degree cross-shuttle transfer mechanism.
Pallet outfeed conveyor – 1.83-m (6-ft) L gravity-fed type.
Finished part exit conveyor – 2.25-m (7.4-ft) L belt-type.
Sprue picker mounted on IMM machine.
Custom end-of-arm tool – multi-function mechanical gripper.
Static bar rotation and checking station.
Cell guarding package that meets ANSI/RIA R15.06-1999 safety standard, including 2.44 m (8') high wire perimeter safety fence; (2) access gates with positive break safety switches and plugs; (3) conveyor pass-through openings (protected by three-sided enclosures to limit operator reach into the cell); dual-channel safety hardware for access gates; and a four-color stack light with audible alarm.

Fixtures/Tooling Details

Motoman Robotics provided custom end-of-arm tooling consisting of a multi-function gripper with three sets of mechanical jaws. Two O.D. grippers pick up link bars and two I.D. grippers on extendable cylinders pick journals from the manually loaded pallet. Two additional O.D. grippers unload finished (molded) parts from the IMM to the exit conveyor. Changeover for each part requires relocation of the grippers for the proper part placing locations. Gripper presents link bars to a laser through-beam checking station that checks for correct gripper details, and then checks flipped link bar for proper part type and part orientation. Gripper includes sensors for open/closed and cylinder extended/ retracted conditions.